US3786334A - Magnetic pulse compression radio-frequency generator apparatus - Google Patents
Magnetic pulse compression radio-frequency generator apparatus Download PDFInfo
- Publication number
- US3786334A US3786334A US00171174A US3786334DA US3786334A US 3786334 A US3786334 A US 3786334A US 00171174 A US00171174 A US 00171174A US 3786334D A US3786334D A US 3786334DA US 3786334 A US3786334 A US 3786334A
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- US
- United States
- Prior art keywords
- pulse compression
- circuit
- magnetic pulse
- circuits
- charging
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/505—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means
- H02M7/515—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only
- H02M7/523—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only with LC-resonance circuit in the main circuit
Definitions
- the present invention relates to methods of and apparatus for radio-frequency pulse compression, being more particularly directed to magnetic pulsecompression radio-frequency generators employing pulsed sequential techniques.
- the pulsed sequential technique and type of basic apparatus described in the said Rines patent is often referred to as the sequential inverter, and is particularly useful when employing SCRs in the frequency range above approximately 20 kHz.
- the basic reason for using the sequential method when employing SCRs resides in the long recovery time compared to the turnoff time of these devices.
- a basic problem with the SCR sequential inverter is the di/dt (rate of change of forward current) rating. Because di/dt is proportioned to frequency, the pulse current rating of SCRs is greatly reduced at high frequencies. This decreased rating starts at about kHz for high-current SCRs. It is known that by the use of magnetic pulse compression techniques, SCRs used in other applications can be operated at maximum pulse current rating; for example, for applications above 100 kHz, an order of magnitude increase in output power can, indeed, be thus obtained.
- Conventional magnetic pulse compression circuits however, unfortunately cannot be used in sequential inverter applications. The output of an individual pulse compression circuit is a unipolar or DC pulse; whereas, the output of a sequential inverter is of alternating polarity. In order to obtain the alternating polarity output and to generate the sequential pulse train, the pulse generators are connected in parallel at the output. But the interaction resulting from this interconnection has heretofore made the use of ordinary magnetic pulse compression networks impossible in these applications.
- a further object is to provide a novel radio-frequency generating apparatus.
- the invention embraces sequential inverters, preferably SCR-controlled, connected with corresponding magnetic pulse compression circuits in a novel compatable way to enable feeding a common load without interaction.
- FIG. 1 of which is a schematic circuit diagram of a preferred embodiment
- FIG. 2 is an explanatory waveform diagram illustrating voltage and current waveforms of the magnetic pulse compression generator apparatus of FIG. 1.
- a novel magnetic SCR pulse compression circuit is used that has been found to have a low output impedance during the interval of output pulse generation, and a high impedance during the interval between output pulses.
- no deleterious interaction effects before discussed, can take place between the pulse circuits, and they can fortuitously be connected together at the output without mutual interaction for such purposes as employment in sequential inverters.
- a preferred embodiment of this magnetic pulse compression network is shown in FIG. 1, comprising SCR charging circuits I through 1,, connected in cascade with and followed by respective magnetic pulse compression circuits I I',,. Any plurality or number n of similar SCR charging circuits and magnetic pulse compression circuits can be used; but the two circuit system shown in FIG. 1 has the minimal number of SCR charging and magnetic pulse compression circuits for the practice of the invention.
- the SCR charging circuits at successive locations I 1, are shown similarly constructed, each provided with respective series input inductances L and L and trigger-activated SCRs, indicated at SCR and SCR connected with the positive terminal of a DC power supply source
- First energy storage charging circuits are provided by the elements L SCR and L SCR in combination with respectivecapacitors C and C each returned to the negative terminal of the source
- Second charging circuits are connected to follow the first charging circuits, comprising respective SCRs indicated at SCR: and SCR series inductances L and L and capacitors C and C
- Respective pulse compression reactors SR and SR provided with respective diodes D and D are connected to the second charging circuits of the circuits I I,,, and feed the load Z through respective output transformers T
- the time interval of charging C is labeled 1,, and it will be seen that the charging current i, is half a sine wave and that the voltage on C is a negative cosine wave offset by approximately ra -vi (8
- the time interval 1' is equal to one-half the period of the resonance frequency V I lL C
- the charge condition is illustrated by and signs in FIG. 1 adjacent capacitors C and C (and C, and C in vertical alignment with the state number@. This charging period ends at time t, and the circuit remains idle during the time interval labelled as state@.
- SCR is reversely biased, the interval lasting for a time TR which is sufficient to allow the SCR to recover to the off state.
- this time is of the order of 40 to 50 usec; and for fast-recovery SCRs, this time may be reduced to to 20 usec.
- the recovery interval ends at time t when SCRz, is rendered conductive or turned on by means of a trigger signal, such as of the sequential type described in the before-mentioned Letters Patent.
- the charge on C is accordingly discharged or transferred to C and vice versa. This interchange of charge is perfect if the capacitors have the same capacitance value and if no loss takes place during charge transfer.
- the interval of charge interchange is labeled r, in FIG.
- 2 and its length is determined by two considerations: first, the optimizing of the pulse current capability of the SCR and secondly, the minimizing of the magnetic pulse compression required of the saturable reactor SR of the following magnetic pulse compression circuit I. As shown, 1 is somewhat smaller than 1,, though this is not always necessary.
- the saturable reactor SR Prior to interval 1- the saturable reactor SR, which typically may consist of a magnetic toroidal core with rectangular hysteresis loop (i.e., 51% iron, 50 nickel), such as those marketed under the trade names Deltamax or Orthonol, is biased into negative saturation by the bias current I, applied to the upper winding of reactor SR as is well known.
- the bias current I applied to the upper winding of reactor SR as is well known.
- the voltage on capacitor C reverses polarity and becomes positive at t
- the shaded volt-time area, labeled J'e,dt in FIG. 2 drives the saturable reactor SR from negative to positive saturation.
- the volt-time integral is proportional to the magnetic flux in the core.
- the saturable reactor SR saturates and becomes a very low inductance.
- the charge on capacitor C discharges very rapidly into the load during the relatively short time interval labeled T at state
- the charge condition is shown on the capacitors vertically above the state 6) notation in FIG. 1.
- This corresponds to the shaded negative output pulse between oscillations 36 and 2 (state in the lower waveform of FIG. 2.
- the resulting pulse compression is represented by the ratio r lr
- the output stage is designed such that the resonant circuit formed by capacitor C the saturated inductance of SR and the load is underdamped.
- the pulse circuit When SCR has recovered during period T the pulse circuit again is ready to start the generation of an output pulse.
- the period of operation (T,,,,,,,,,,,,) of the pulse circuit is the sum of the time intervals 7,, Ti e 1-2, T and TRECT
- the number of pulse circuits n required to generate a continuous wave (C.W,) by sequential discharging of stored energy at successive locations I I I,, I,, is equal to the ratio of T I0 T3.
- the pulse circuits are operating into a high Q load 2,, and amplitude ripple on the output waveform is acceptable, then the pulse circuits need not generate every half-cycle. In this manner, the number of pulse circuits may be reduced. These pulse circuits may also be used to generate RF pulses with prescribed shape such as used in Loran navigation systems and the like, in which cases, the number n of pulse circuits is determined by the length and shape of the RF pulse.
- Magnetic pulse compression radio-frequency generator apparatus having, in combination, sequential inverter means having a plurality of energy storage and discharge circuits disposed at a plurality of locations, each such circuit being provided with a magnetic pulse compression circuit, means for connecting all of the plurality of magnetic pulse compression circuits to a common load, and means comprising gated trigger means connected in each energy storage and discharge circuit for controlling the impedance of the corresponding magnetic pulse compression circuit in order to generate sequential compressed pulses in the plurality of magnetic pulse compression circuits for application to the said common load, the storage circuits of said sequential inverter means each comprising cascaded first and second resonant charging circuits each provided with said gated trigger means for controlling the transfer of the charge stored therein, said trigger means of said second resonant charging circuit having DC power supply means for reverse biasing the lastmentioned trigger means to maintain the same nonconductive for a period of time after it has been rendered conductive.
- each of the second charging circuits is connected with a corresponding one of the magnetic pulse compression circuits comprising a saturable reactor, diode and output transformer.
- the first resonant charging circuit comprises an inductance, a semiconductor controlled rectifier, and a capacitance in series across a source of energy
- the second resonant charging circuit comprises a semiconductor controlled rectifier, an inductance, and a capacitance in series across the first-mentioned capacitance
- each of said magnetic pulse compression circuits comprises a saturable reactor in series with a rectifier across the second-mentioned capacitance.
- Apparatus as claimed in claim 5 and in which said DC power supply means comprises means connected to said capacitances for charging said capacitances to voltages which are of polarity opposite to the polarity of the voltage to which the first-mentioned capacitance is charged by said source and which are of relative magnitude to apply a reverse voltage to the last-mentioned controlling means comprises means for reducing the series impedance of said reactor and said rectifier to a low value for discharging the stored energy through the pulse compress iqncircuit to said load and for thereafter back-biasing said rectifier to isolate the pulse compression circuit from the load.
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
- Generation Of Surge Voltage And Current (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
- Dc-Dc Converters (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17117471A | 1971-08-12 | 1971-08-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3786334A true US3786334A (en) | 1974-01-15 |
Family
ID=22622819
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00171174A Expired - Lifetime US3786334A (en) | 1971-08-12 | 1971-08-12 | Magnetic pulse compression radio-frequency generator apparatus |
Country Status (9)
Country | Link |
---|---|
US (1) | US3786334A (xx) |
CA (1) | CA964733A (xx) |
DE (1) | DE2239691C3 (xx) |
FR (1) | FR2150069A5 (xx) |
GB (1) | GB1343244A (xx) |
IT (1) | IT961950B (xx) |
NL (1) | NL7210840A (xx) |
NO (1) | NO138426C (xx) |
SU (1) | SU503566A3 (xx) |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3946300A (en) * | 1973-11-08 | 1976-03-23 | Pillar Corporation | High frequency power supply |
US4001598A (en) * | 1975-12-29 | 1977-01-04 | Megapulse Incorporated | Sequential power supply and method for rf pulse generation |
US4017705A (en) * | 1975-03-28 | 1977-04-12 | Sergei Nikolaevich Bazhenov | Impulse current generator for electroerosion machining of metals |
FR2454225A1 (fr) * | 1979-04-09 | 1980-11-07 | Megapulse Inc | Generateur de haute tension et procede de generation repetitive d'impulsions a haute tension |
US4255668A (en) * | 1978-03-30 | 1981-03-10 | Emi Limited | Pulsed power supplies |
US4423419A (en) * | 1980-10-20 | 1983-12-27 | Megapulse Incorporated | Pulsed, pseudo random position fixing radio navigation method and system and the like |
US4674022A (en) * | 1986-07-01 | 1987-06-16 | Megapulse, Inc. | SCR priming and sweep-out circuit apparatus |
US4684820A (en) * | 1985-02-13 | 1987-08-04 | Maxwell Laboratories, Inc. | Symmetrically charged pulse-forming circuit |
US4743912A (en) * | 1985-06-24 | 1988-05-10 | Megapulse Inc. | Method of and apparatus for reducing cycle slippage errors in Loran-C and similar radio-frequency signal reception, particularly in vehicles undergoing acceleration |
EP0271174A2 (en) * | 1986-11-12 | 1988-06-15 | Megapulse Incorporated | Apparatus for radio-frequency generation in resonator tank circuits |
US4791422A (en) * | 1986-07-14 | 1988-12-13 | Megapulse Incorporated | Methods of and apparatus for measuring time of arrival of remote Loran-C and related signals and effective time of transmission of local signals at transmitter sites |
US4928020A (en) * | 1988-04-05 | 1990-05-22 | The United States Of America As Represented By The United States Department Of Energy | Saturable inductor and transformer structures for magnetic pulse compression |
US5157272A (en) * | 1986-01-17 | 1992-10-20 | British Aerospace Public Limited Company | Pulse forming networks |
EP0550757A1 (en) * | 1991-06-28 | 1993-07-14 | Hitachi Metals, Ltd. | Pulse generator and dust collector using same |
WO1998001950A1 (en) * | 1996-07-09 | 1998-01-15 | Megapulse Inc. | Solid state pulse generating apparatus |
US5969439A (en) * | 1998-04-09 | 1999-10-19 | Megapulse, Incorporated | Pulse generator apparatus for RF pulse generation in tuned loads including series regulation and capacitor clamping method therefor |
US6154383A (en) * | 1999-07-12 | 2000-11-28 | Hughes Electronics Corporation | Power supply circuit for an ion engine sequentially operated power inverters |
DE102010001934A1 (de) | 2010-02-15 | 2011-08-18 | Helmholtz-Zentrum Dresden - Rossendorf e.V., 01328 | Vorrichtung zur Stromverstärkung für die elektromagnetische Pulsumformung und Verwendung |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2135547B (en) * | 1983-01-22 | 1986-05-14 | Marconi Co Ltd | Pulse circuits |
GB2140236B (en) * | 1983-05-20 | 1987-08-05 | Marconi Co Ltd | Pulse generators |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2869004A (en) * | 1954-12-17 | 1959-01-13 | British Thomson Houston Co Ltd | Pulse generating electrical circuit arrangements |
US3193693A (en) * | 1959-12-29 | 1965-07-06 | Ibm | Pulse generating circuit |
US3211915A (en) * | 1960-04-05 | 1965-10-12 | Westinghouse Electric Corp | Semiconductor saturating reactor pulsers |
US3290581A (en) * | 1963-06-28 | 1966-12-06 | Westinghouse Electric Corp | Bridge type sine wave generator |
GB1058839A (en) * | 1964-06-12 | 1967-02-15 | Westinghouse Brake & Signal | Improvements relating to inverter or frequency changing circuits |
US3323076A (en) * | 1963-03-26 | 1967-05-30 | Westinghouse Brake & Signal | Relaxation inverter circuit arrangement |
GB1136376A (en) * | 1965-02-24 | 1968-12-11 | Licentia Gmbh | Electric current converter comprising an oscillatory circuit |
US3422341A (en) * | 1965-06-18 | 1969-01-14 | Toshio Kurimura | Rectifying apparatus for producing constant d.c. output voltage |
-
1971
- 1971-08-12 US US00171174A patent/US3786334A/en not_active Expired - Lifetime
-
1972
- 1972-05-30 CA CA143,443A patent/CA964733A/en not_active Expired
- 1972-06-01 GB GB2565972A patent/GB1343244A/en not_active Expired
- 1972-08-03 SU SU1818101A patent/SU503566A3/ru active
- 1972-08-08 NL NL7210840A patent/NL7210840A/xx unknown
- 1972-08-10 IT IT52099/72A patent/IT961950B/it active
- 1972-08-11 NO NO2865/72A patent/NO138426C/no unknown
- 1972-08-11 DE DE2239691A patent/DE2239691C3/de not_active Expired
- 1972-08-11 FR FR7229030A patent/FR2150069A5/fr not_active Expired
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2869004A (en) * | 1954-12-17 | 1959-01-13 | British Thomson Houston Co Ltd | Pulse generating electrical circuit arrangements |
US3193693A (en) * | 1959-12-29 | 1965-07-06 | Ibm | Pulse generating circuit |
US3211915A (en) * | 1960-04-05 | 1965-10-12 | Westinghouse Electric Corp | Semiconductor saturating reactor pulsers |
US3323076A (en) * | 1963-03-26 | 1967-05-30 | Westinghouse Brake & Signal | Relaxation inverter circuit arrangement |
US3290581A (en) * | 1963-06-28 | 1966-12-06 | Westinghouse Electric Corp | Bridge type sine wave generator |
GB1058839A (en) * | 1964-06-12 | 1967-02-15 | Westinghouse Brake & Signal | Improvements relating to inverter or frequency changing circuits |
GB1136376A (en) * | 1965-02-24 | 1968-12-11 | Licentia Gmbh | Electric current converter comprising an oscillatory circuit |
US3422341A (en) * | 1965-06-18 | 1969-01-14 | Toshio Kurimura | Rectifying apparatus for producing constant d.c. output voltage |
Cited By (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3946300A (en) * | 1973-11-08 | 1976-03-23 | Pillar Corporation | High frequency power supply |
US4017705A (en) * | 1975-03-28 | 1977-04-12 | Sergei Nikolaevich Bazhenov | Impulse current generator for electroerosion machining of metals |
US4001598A (en) * | 1975-12-29 | 1977-01-04 | Megapulse Incorporated | Sequential power supply and method for rf pulse generation |
US4255668A (en) * | 1978-03-30 | 1981-03-10 | Emi Limited | Pulsed power supplies |
FR2454225A1 (fr) * | 1979-04-09 | 1980-11-07 | Megapulse Inc | Generateur de haute tension et procede de generation repetitive d'impulsions a haute tension |
US4274134A (en) * | 1979-04-09 | 1981-06-16 | Megapulse Incorporated | Method of and apparatus for high voltage pulse generation |
US4423419A (en) * | 1980-10-20 | 1983-12-27 | Megapulse Incorporated | Pulsed, pseudo random position fixing radio navigation method and system and the like |
US4684820A (en) * | 1985-02-13 | 1987-08-04 | Maxwell Laboratories, Inc. | Symmetrically charged pulse-forming circuit |
US4743912A (en) * | 1985-06-24 | 1988-05-10 | Megapulse Inc. | Method of and apparatus for reducing cycle slippage errors in Loran-C and similar radio-frequency signal reception, particularly in vehicles undergoing acceleration |
US5157272A (en) * | 1986-01-17 | 1992-10-20 | British Aerospace Public Limited Company | Pulse forming networks |
US4674022A (en) * | 1986-07-01 | 1987-06-16 | Megapulse, Inc. | SCR priming and sweep-out circuit apparatus |
US4791422A (en) * | 1986-07-14 | 1988-12-13 | Megapulse Incorporated | Methods of and apparatus for measuring time of arrival of remote Loran-C and related signals and effective time of transmission of local signals at transmitter sites |
EP0271174A3 (en) * | 1986-11-12 | 1989-06-07 | Megapulse Incorporated | Method of and apparatus for radio-frequency generation in resonator tank circuits. |
AU595880B2 (en) * | 1986-11-12 | 1990-04-12 | Megapulse Incorporated | Method of and apparatus for radio-frequency generation in resonator tank circuits excited by sequential pulses of alternately opposite polarity |
EP0271174A2 (en) * | 1986-11-12 | 1988-06-15 | Megapulse Incorporated | Apparatus for radio-frequency generation in resonator tank circuits |
US4767999A (en) * | 1986-11-12 | 1988-08-30 | Megapulse, Inc. | Method of and apparatus for radio-frequency generation in resonator tank circuits excited by sequential pulses of alternately opposite polarity |
US4928020A (en) * | 1988-04-05 | 1990-05-22 | The United States Of America As Represented By The United States Department Of Energy | Saturable inductor and transformer structures for magnetic pulse compression |
EP0550757B1 (en) * | 1991-06-28 | 2001-10-10 | Hitachi Metals, Ltd. | Pulse generator and dust collector using same |
EP0550757A1 (en) * | 1991-06-28 | 1993-07-14 | Hitachi Metals, Ltd. | Pulse generator and dust collector using same |
WO1998001950A1 (en) * | 1996-07-09 | 1998-01-15 | Megapulse Inc. | Solid state pulse generating apparatus |
US5734544A (en) * | 1996-07-09 | 1998-03-31 | Megapulse, Inc. | Solid-state pulse generating apparatus and method particularly adapted for ion implantation |
US5969439A (en) * | 1998-04-09 | 1999-10-19 | Megapulse, Incorporated | Pulse generator apparatus for RF pulse generation in tuned loads including series regulation and capacitor clamping method therefor |
US6154383A (en) * | 1999-07-12 | 2000-11-28 | Hughes Electronics Corporation | Power supply circuit for an ion engine sequentially operated power inverters |
DE102010001934A1 (de) | 2010-02-15 | 2011-08-18 | Helmholtz-Zentrum Dresden - Rossendorf e.V., 01328 | Vorrichtung zur Stromverstärkung für die elektromagnetische Pulsumformung und Verwendung |
EP2383756A2 (de) | 2010-02-15 | 2011-11-02 | Helmholtz-Zentrum Dresden - Rossendorf e.V. | Vorrichtung zur Stromverstärkung für die elektromagnetische Pulsumformung und Verwendung |
Also Published As
Publication number | Publication date |
---|---|
NL7210840A (xx) | 1973-02-14 |
DE2239691C3 (de) | 1975-03-27 |
SU503566A3 (ru) | 1976-02-15 |
NO138426B (no) | 1978-05-22 |
NO138426C (no) | 1978-08-30 |
GB1343244A (en) | 1974-01-10 |
FR2150069A5 (xx) | 1973-03-30 |
DE2239691A1 (de) | 1973-02-22 |
CA964733A (en) | 1975-03-18 |
DE2239691B2 (de) | 1974-08-08 |
IT961950B (it) | 1973-12-10 |
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